I think I have a similar problem with Aiji cordless dial up, cannot connect through a router but all have to go direct to comp.
What I have to do all the time I go on and off is, uncheck DHCP and enter the IP address you want, actually showing on the DCC, then save . after that do the connection and GREEN bar will come on connected.
only when one of the two goes off I find the IP address changes again on the DM. Try check off the DHCP and enter IP manually on DM, also you can choose to enter the number on the DM ip,manually on the dcc. or search on the dcc and accept.